02274nas a2200241   4500008004100000022001400041245014400055210006900199260007900268300000800347490000700355520135400362653002901716653001001745653001001755653002101765100002201786700002901808700002601837700001901863700002101882856012901903       2014                        eng d  a0141-022900aNew role for penicillin acylases: degradation of acyl homoserine lactone quorum sensing signals by Kluyvera citrophila penicillin G acylase0 aNew role for penicillin acylases degradation of acyl homoserine   a360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USAbELSEVIER SCIENCE INCcMAR  a1-70 v563 a<p>Use of penicillin acylases for the production of semi-synthetic penicillins is well-known. Escherichia coli penicillin G acylase (EcPGA) has been extensively used for this purpose; however, Kluyvera citrophila penicillin G acylase (KcPGA) is assumed to be a better substitute, owing to its increased resilience to extreme pH conditions and ease of immobilization. In the present article we report a new dimension for the amidase activity of KcPGA by demonstrating its ability to cleave bacterial quorum sensing signal molecules, acyl homoserine lactones (AHL) with acyl chain length of 6-8 with or without oxo-substitution at third carbon position. Initial evidence of AHL degrading capability of KcPGA was obtained using CV026 based bioassay method. Kinetic studies performed at pH 8.0 and 50 degrees C revealed 3-oxo-C6 HSL to be the best substrate for the enzyme with V-max and K-m values of 21.37+0.85 mM/h/mg of protein and 0.1+0.01 mM, respectively. C6 HSL was found to be the second best substrate with V-max. and K-m value of 10.06+0.27 mM/h/mg of protein and 0.28+0.02 mM, respectively. Molecular modeling and docking studies performed on the active site of the enzyme support these findings by showing the fitting of AHLs perfectly within the hydrophobic pocket of the enzyme active site. (c) 2013 Elsevier Inc. All rights reserved.</p>10aAcyl homoserine lactones10aCV02610aKcPGA10aQuorum quenching1 aMukherji, Ruchira1 aVarshney, Nishant, Kumar1 aPanigrahi, Priyabrata1 aSuresh, C., G.1 aPrabhune, Asmita  uhttps://library.ncl.res.in/content/new-role-penicillin-acylases-degradation-acyl-homoserine-lactone-quorum-sensing-signals-0